In a wide range of electric motor applications, the motors are provided in a receiving housing serving as a motor housing which is then used to further attach the electric motor. This receiving housing is also used to decouple motor vibrations. For example, fan motors for heating and air conditioning systems which are typically used in motor vehicles are usually vibration-decoupled with respect to the vehicle. The goal is to limit the transmission of structure-borne noise from the electric motor or fan unit to the vehicle body and thus to the passenger compartment.
According to common methods for mounting motors of this type, the electric motor is introduced, for example, into a receiving housing serving as a motor housing, elastic isolation means being provided between the electric motor and the receiving housing so that it is possible to decouple the motor vibrations from the motor housing and thus, for example, from a vehicle body. A flange for securely connecting the motor to the air conditioning system, for example via a carrier part formed on the body, is typically provided on the motor mount itself.
Published German patent document DE 43 34 124 describes a device for accommodating an electric motor which achieves an especially low-vibration and thus noise-damping effect by providing, between the inner walls of this receiving device and the outer walls of the motor housing facing the device, at least one elastic damping element which is supported on the walls of the receiving device and the motor housing facing each other.
Another critical point relating to the transmission of the structure-borne noise generated by the electric motor to the motor housing and thus to the vehicle body is the plug-and-socket connection typically used for supplying electric power to the electric motor. The motor is provided with an integrated plug-and-socket connection. Because the motor is completely enclosed by the motor mount, the cable connection for supplying power is produced by a plug that is typically latched to the motor housing from the outside. The mechanical latching system is used to absorb the cable or plug extraction forces occurring during fan assembly and operation.
An air conditioning fan motor as well as a receiving housing in which a plug element for supplying electric power to the driving motor is passed through the receiving housing is described in published International patent document WO 00/48 293. The corresponding opening in the receiving housing of the electric motor is just large enough to insert the connecting plug element in a form-locked manner through this receiving opening. The system according to WO 00/48 293 thus prevents air taken in between the plug element and the receiving housing for the electric motor from exiting the fan. WO 00/48 293 also proposes to insert, between the plug element and the receiving housing, a sealing element which attaches the plug to the receiving housing and also prevents undesirable exiting of air at this point.
An object of the present invention is to prevent noises and vibrations generated by the electric motor from being coupled into the motor housing, or to substantially dampen them in their penetration.